This invention relates to a switch for energizing an electric motor of a wiper system.
A switch of this kind is known from practice. Starting from a parking position the switch is adjustable by turning a switch lever in three successive operating positions. The first operating position thereby corresponds to an intermittent mode of operation in which a wiping action with a low wiper speed interrupted by interval times is effected. The following operating position corresponds to a first mode of continuous operation, in which a continuously low wiper speed is effected and the then following position corresponds to a second mode of continuous operatio in which a continuously high wiper speed is effected. The stationary contacts associated with the two modes of continuous operation of this construction are arranged one behind the other on a first contact path, whereas the stationary contacts associated with the intermittent mode of operation are located on a second contact path positioned beside the first contact path. The stationary contacts on the first contact path can thereby be acted upon in pairs by a first bridging contact and the stationary contacts on the second contact path can be acted upon in pairs by a second bridging contact. A disadvantge of this switch is that upon a failure of a pair of stationary contacts or of a part of this pair the associated mode of operation can no longer be effected. It is true that a failure of this kind does not happen very frequently in practice, however recently switches have been increasingly required in which a failure of this kind is even less probable and which therefore have an increased operational reliability in comparison with customary switches.